ISRO to usher in a new era of Satellites with Electric Propulsion

Indian Space Research Organisation (Isro) has been working on a new propulsion system that is set to usher in a new era of cost effective satellite launches.

Known as electric propulsion (EP) system, this technology converts solar energy into electrical energy which, in turn, is used to change the velocity of a satellite in space. It reduces the use of chemical propellant in a launch vehicle.

EP system was first used as a technology demonstrator in Gsat-9 or the South Asia Satellite launched on May 5, which was PM Narendra Modi’s brainchild.

This chemical fuel is required for transferring the communication satellite from the geosynchronous transfer orbit (where it is placed by a rocket) to the geostationary orbit (36,000km away from the earth).

It also helps in orbit correction and maintaining a satellite on its path for its life duration of 10-12 years.

However, the new electric propulsion system reduces the usage of chemical propellant to just 100-200kg as the former serves as the back-up power for correcting the orbit of the spacecraft.

“The EP system gives small but accurate thrust to a satellite in its orbit. It can be used for course correction of a satellite during its life duration,” said a top source in Isro.

“The EP system basically converts solar energy into electrical energy and then kinetic energy by generating thrust that propels a satellite. The system just needs a solar panel and components for charging ions,” he said.

With the new system, we can reduce the quantity of chemical propellant carried on a satellite and thus carry a heavier payload to space,” said Dr K Sivan, director of Thiruvananthapuram-based Vikram Sarabhai Space Centre.

“The EP system, also being used by Nasa and Russia, has the capability to eventually lower the cost of launches and can also be used for deep-space and interplanetary missions,” he said.

After the June 5 launch of its ‘Baahubali’ GSLV Mk III rocket, Isro has acquired the capability to launch a satellite of up to 4 tonnes into the geo orbit.

“However, a G-series satellite will be launched from the spaceport in French Guiana, Kourou, as this communication satellite weighs 5.6 tonnes,” says Tapan Misra, director of Ahmedabad-based Space Applications Centre.

“Another satellite Gsat-20, which is five times more powerful than the one that will be launched from French Guiana, is based on a new technology that reduces its weight to just 3.5 tonnes.

This satellite will be launched by our ‘Baahubali’ GSLV Mk III,” Misra said.